What is meant by the term "deluge system" in fire protection?

The term "deluge system" in fire protection refers to a system where all sprinkler heads discharge simultaneously. This type of system is typically used in high-hazard areas where rapid fire growth is a concern, such as in chemical processing plants or warehouses storing flammable materials.

In a deluge system, the sprinkler heads are open, meaning they do not have individual heat-sensitive elements that activate them. Instead, the entire system is activated by a fire detection mechanism, such as smoke detectors or heat detectors. Once triggered, water is released through all the sprinkler heads at once, providing a significant amount of water coverage to combat a rapidly growing fire.

This design contrasts with conventional sprinkler systems, which activate only those sprinkler heads that sense high temperatures due to a fire. The unique operational characteristic of deluge systems allows for a more aggressive initial response to prevent the spread of fire in high-risk environments.